Timing device



May 26, 1925. 1,539,684

F. s. MARCELLUS ET AL TIMING DEVICE Fild Sept. '7. 1923 2 Sheets-Sheet 1 Fig. l.

Inventors: y Fredrick STfiarcellus, Jesse J. Powers,

Their Attorneq.

May 26, 1925. 1,539,684

F. s. MARCELLUS ET AL TIMING DEVICE Filed Sept. 7. 1923 2 Sheets-Sheet 2 Fig. 6.

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Ja I 0% @3 t Pi 7. 2 SIGNAL/N6 ()l/PCU/T Inventors:

Fredrick Smarcellus,

Jesse J. Powers,

Their Attorney.

Patented May 26, 1925.

UNITED STATES PATENT OFFICE.

FBEDRIOK S. IIARCELLUS AID JESSE J. POW'ERS, OF SCHENEUPADY, NEW YORK, ASSIGNOBB TO GENERAL ELECTRIC COMPANY, 'A CORPORATION OF NEW YORK.

. ammo omen Application fled September 7, 1988. Serial No. 681,456.

To all whom it may concern:

- Be it known that we, FREDRICK S. MAR- oELLUs and Jnssn J .Pownns, citizens of the United States, residing at Schenectady, in

the county of Schenectady, State of New York, have invented certain new and useful Improvements in Timing Devices, of which the following is a specification.

Our invention relates to timing devices and in particular to a timing device for obtaining timed electrical impulses.

The object of our invention is to provide a device of the character described which will be highly accurate, simple and inexpensive in construction and operation and one in which the time of the impulse may be readily changed. In carrying our invention into effect, we make use of an escapement clock as the timing element and actuate electric contacts by the kinetic energy of the escapement which energy is ordinarily used up in bringing the escapement mechanism to rest at the end of an oscillation. The contacting mechanism is so arranged that errors due to back lash and friction are entirely eliminated, yet the contacting device is positive in its action and is readily adjustable for different periods.

The features of our invention which we believe to be novel and patentable will be pointed out in the claim a pended hereto. A practical embodiment 0 our invention will now be described in connection with the accompanying drawings in which Fig. 1 represents an exploded view of a clock escapement to which our invention is applied; Figs. 2, 3 and 4 illustrate different operating positions of the contacting device shown in Fig. 1; Fig. 5 represents a double contactor incorporating the invention; Fig. 6 shows a portable timing device built in accordance with our invention; and Fig. 7 shows electrical connections appropriate to such a device.

Referring now to the drawings, in which like parts are designated by like reference characters. throughout, and more in particw lar to Fig. 1, we have shown the essential parts of a well known type of clock work comprising a main spring 10 with 1ts driving gear 11, geared through wheel 12 to the escapement pinion 13 of a balance wheel type escapement. The escapement mechanlsm comprises the escape wheel 14, the anehor escapement 15, the forked lever 16 with its stop pins 17, the balance wheel 18 and the balance spring 19, together with the details of this well known type of escapement. The escapement serves, as is well understood, to let down the main spring 10 at a uniform rate. The pallets of the escapement 15 are so shaped and arranged that sufiicient energy is conveyed therethrough from the main spring 10 and the intermediate parts to the balance wheel 18 to give said wheel the necessary impulses to keep the same in oscillation in a well understood manner. In order that the operation of the escapement may be positive and accurate, the stop pins 17 are provided tolimit the oscillating movement of.v the forked lever 16. Due to the connection of the forked end of lever 16 with the balance wheel, the pins 17 serve to absorb the kinetic energy of the balance wheel at the ends of its oscillations.

According to our invention part or all of the energy ordinarily absorbed by the stop pins 17 is used to actuate an electric contactor. This contactor comprises an angular arm 20 secured to the escapement shaft 21 by means of an insulating bushing 22. A contact piece 23 is secured to arm 20 so that its free end 24 will have a slight oscillatory movement when the shaft 21 oscillates. The arm 20 and contact piece 23 are preferably made of resilient conducting material. This contact arm and contact may cooperate With a stationary contact if desirable. However, we prefer to make the cooperating contact in the form of a wheel driven by the clock work in order to obtain various different time period adiustments. Such a wheel is shown at 27 secured to shaft 25 of the clock work by means of thumb screw 26. Ihe periphery of wheel 27 constitutes the other member of the contactor. As illustrated, the periphery of this wheel is provided with teeth, although this is not essential unless adjustments in the time period are desired. The relation of wheel 27 and 100 contact arm 23 is such that the end 24 of arm 23 makes contact with the periphery of wheel 27 at the downward extremity of the oscillation of said arm; that is to say, when lever 16 abuts against the lower stop 17. The contacting position is illustrated in Fig. 2. It will thus be evident that by properly adjusting the parts, part or all of the energy which is ordinarily absorbed by the lower stop 17 may be absorbed by reason of the end 24 of contact arm 23 coming in contact with the periphery of wheel 27. The resiliency of arm 23 makes this a firm contact with a slight wiping action so that it may serve to make and break an electric circuit. As the lever 16 swings to its upper extremity, the contact arm 23 is lifted away from the periphery of wheel 27 as illustrated in Figs. 1 and 3.

If the periphery of the wheel 27 is without teeth, a contact will be made for every downward oscillation of contact arm 23 and it may thus serve to send timed electric impulses which, with the usual escapement, will be every half second. It will be observed that the contact wheel 27 is arranged to be driven by the clock work so that there will be a fixed relation between its speed of rotation and the oscillations of contact arm 23. It will therefore be evident that by providing the periphery of the Wheel with teeth arranged to contact with arm 23 in its contacting position, the timing of the impulses may be varied, as desired, either by changing the gear ratio between shaft 25 and the escapement, or by changing the spacing of the teeth on the wheel, or by both methods. Let us assume that shaft 25 is geared to make one revolution per minute when the escapement makes a complete oscillation every half second. Then, if wheel 27 is provided with 60 evenly spaced teeth, we will obtain by this arrangement a contact every second. This will be evident from a consideration of Figs. 2, 3 and 4. In Fig. 2 contact is being made be tween arm 23 and tooth I. Fig. 3 represents the relative positions of the parts as contact arm 23 swings up to the other extremity of its oscillation. Fig. 4 represents the relative positions of the parts as arm 23 swings down again. During the one-half second interval required to change from the position of Fig. 2 to the position of Fig. 4, wheel 27 has been rotated by the clock work of a revolution so that the end of contact arm 23 now comes to rest at the end of its downward swing between teeth I and II without making contact, the momentum of the parts of the escapement being stopped in this case by the lower stop pin 17 in the usual manner. Wheel 27 may be readily changed by the removal of thumb screw 26. If contacts are desired every (garter-second, contact 23 should be replaced y double arm contact as represented at 23' in Fig. 5, arranged to make contact at both extremities of its oscillation with a wheel 27 provided with double the number of teeth, or with a solid periphery.

In Figs. 2 to 4 inclusive, we have shown a toothed wheel with one tooth missing, so that once every minute the contact device will miss a contact. thereby distinguishing the minute intervals on the impulses sent out. V Other arrangements of the contacts and the timing relation will occur to those skilled in the art whereby it will be possible to obtain any desired sequence of timed impulses or signals.

It will be evident that at the instant contact is made, the wheel 27 comes to rest and that when it is being driven by clock work,

it is absolutely free from any frictional contact so that the deviceintroduces no additional load on the clock and produces no back lash between gears, so that the timing impulses will be absolutely correct if the clock is correct. The addition of the simple parts of our contacting mechanism to most any type of existing clock may be readily accomplished without any change in the clock itself.

In Fig. 7 we have shown an appropriate wiring diagram for the electrical connections. In this figure. one of the bearings of the clock work is electrically connected to a source of potential such as the battery 30. The other side of the battery goes to a switch 31. through a relay coil 32 and to the insulated contact arm 23. Relay 32 operates an armature 33 and switch contacts 34 so as to close a signalling circuit through a suitable source of potential represented as a batterv When it is not desirable to use the timing device for impulses. the switch 31 may be open leaving the clock work running. In Fig. 6 we have represented a portable clock and t ming device incorporating our invention. The usual tvne of spring driven clock is mounted in a suitable case 36. The contacting mechanism consisting of arm 23. wheel 27 and thumb screw 26 are readily accessible when the case is opened. The relay 32 and armature 33 are shown mounted in the case. Switch 31 and appropriate circuit terminals 37 are also preferably mounted in the upper part of the case. The 'device. as thus described. is always ready for instant use either as a clock or as a time contact maker. or as both.

In accordance with the provisions of the patent statutes. we have described the principle of operation of our invention, together with the apparatus which we now consider to represent the best embodiment thereof; but we desire to have it understood that the apparatus shown is only illustrative and that the invention may be carried out by other means.

What we claim as new and desire to secure by Letters Patent of the United States, is

In combination, an escapement clock work,

an escapement shaft therefor, a pair of re- 5 silient electrical contact arms secured to said shaft, and relatively stationary electrical contacts in spaced relation to said esca ment shaft, said resilient contact arms bemg arranged to be respectively oscillated against said relatively stationary contacts to stop 10 the oscillatory movements of said shaft at the extremities of its normal oscillation.

In witness whereof, we have hereunto set our hands this 6th day of September, 1923.

FREDRICK S. MARCELLUS. JESSE J. POWERS. 

